There is nothing like LINQ for Java. … Edit Now with Java 8 we are introduced to the Stream API, this is a similar kind of thing when dealing with collections, but it is not quite the same as Linq. If it is an ORM you are looking for, like Entity Framework, then you can … Read more
No, a List<Dog> is not a List<Animal>. Consider what you can do with a List<Animal> – you can add any animal to it… including a cat. Now, can you logically add a cat to a litter of puppies? Absolutely not. // Illegal code – because otherwise life would be Bad List<Dog> dogs = new ArrayList<Dog>(); … Read more
There is a shorthand that I use that is not very time efficient, but fits on a single line: Set<String> h = new HashSet<>(Arrays.asList(“a”, “b”)); Again, this is not time efficient since you are constructing an array, converting to a list and using that list to create a set. When initializing static final sets I … Read more
NOTE: The mentioned LATEST and RELEASE metaversions have been dropped for plugin dependencies in Maven 3 “for the sake of reproducible builds”, over 6 years ago. (They still work perfectly fine for regular dependencies.) For plugin dependencies please refer to this Maven 3 compliant solution. If you always want to use the newest version, Maven … Read more
Steps for adding external jars in IntelliJ IDEA: Click File from the toolbar Select Project Structure option (CTRL + SHIFT + ALT + S on Windows/Linux, ⌘ + ; on Mac OS X) Select Modules at the left panel Select Dependencies tab Select + icon Select 1 JARs or directories option
One option could be letting your custom class implement the Serializable interface and then you can pass object instances in the intent extra using the putExtra(Serializable..) variant of the Intent#putExtra() method. Actual Code: In Your Custom Model/Object Class: public class YourClass implements Serializable { At other class where using the Custom Model/Class: //To pass: intent.putExtra(“KEY_NAME”, … Read more
A daemon thread is a thread that does not prevent the JVM from exiting when the program finishes but the thread is still running. An example for a daemon thread is the garbage collection. You can use the setDaemon(boolean) method to change the Thread daemon properties before the thread starts.
Kotlin Handler(Looper.getMainLooper()).postDelayed({ //Do something after 100ms }, 100) Java final Handler handler = new Handler(Looper.getMainLooper()); handler.postDelayed(new Runnable() { @Override public void run() { //Do something after 100ms } }, 100);
List myList = new ArrayList(); or with generics (Java 7 or later) List<MyType> myList = new ArrayList<>(); or with generics (Old java versions) List<MyType> myList = new ArrayList<MyType>();
From Understanding Weak References, by Ethan Nicholas: Weak references A weak reference, simply put, is a reference that isn’t strong enough to force an object to remain in memory. Weak references allow you to leverage the garbage collector’s ability to determine reachability for you, so you don’t have to do it yourself. You create a … Read more